Speedometer



sept. 14 wz@ 1,599,768

` D. F. HYLAND SPEEDOMETER Filed July 30, 1925 Patented Sept. 14, 1926.

UNITED STATES DANIEL I". HYLAND, OF ST. LOUIS, MISSOURI.

SPEEDGMETER.

Application filed. July 30,

rlhis invention relates to speedometcrs, such as are used on motor vehicles, and similar devices, and it is more particularly directed toward means for showing when such a vehicle has been improperly driven.

Automobile trucks and similar vehicles are Otten driven by hired chauffeurs who are not the owners of the vehicles. Most truclrs are designed to operate normally at a moderate speed and, while capable ot running at greatly increased speeds, the normal operation thereof-does not contemplate use at a high speed for any considerable length of time. Consequently excessive wear and sometimes actual damage may result from habitually driving the car at an excessive speed. It is desirable, therefore, to provide means which will disclose the tact that a chauii'eur has been driving his car at too high a speed so that a chauffeur who cannot be trusted to handle his car properly can be detected and properly dealt with.

One of the objects of this invention, therefore, is to provide a speedometer which, while indicating the speed at which the car is running in a usual manner, will also indicate when the car has been driven at an excessive speed.

Another object of this invention is to provide such an instrument which after indicating such an excessive speed will maintain such an indication until reset by some authorized person.

Further objects will appear from the detail description taken in connection with the accompanying' drawing, in which:

Figure 1 represents a front view of a speedometer embodying` this invention;

l-ll`igure 2 is a detail showing the indicating dial;

. Figure 3 is a partial section Ataken approximately on line 3 3, Figure 2; and

Figure is a plan view ot the mechanism above the dial.

Referring to the accompanying drawing, the speedometer may be of any ordinary type, such as shown in Figure 1, which shows the front view of a speedometer which as usual is ordinarily mounted on the dash of an automobile and is provided with a front plate 1 having a suitable perforation 2 through which the speed indicating dial may be viewed and perforations 3 and et adapted to disclose the mileage indicamos- 1923. Serial No. 654,594.

The front may be enclosed by a glass cover having a rim 5 secured by means of screws 6 in the usual manner. These screws may-,be provided with suitable seals to prevent un authorized tampering therewith.

ln the ordinary construction of such a speedometer, the speed indicating element or dial 7 is provided usually in the form of an inverted cylindrical cup having the speed indicating circle marked on its cylindrical surface. This dial is mounted on a spindle 8 suitably pivoted in the mechanism and controlled by a spring 9, the inside end ot' which may be connected to the spindle and the other end suitably anchored to a stationary part of the mechanism as, for instance, to a lug 10 on the top plate 11 which carries the upper bearing 12 for the spindle 8. The dial 7 may be provided with a lug 13 adapted to be urged against a suitable stop 1d andthe plate 11 by the spring 9. The spring normally holds the dial in position with the lug 13 against the stop 14C when the car is at rest. This normal position is in.

dicated as the 0 position in Figure 1.

Suitable mechanism for driving the dial 7 tor indicate' the speed of the car is provided as, for instance, the rotating element 15 suitably driven by driving mechanism 16, not shown in detail, which is connected with the ywheels or other moving part of the car,

whose motion is proportionate to that of the car. The element 15 may be pivoted for rotation on the vertical spindle, not shown, and may carry a permanent magnet 17 of the horseshoe type but formed as a circular ring having poles N and S on opposite sides of a slit or gap in the ring. The magnet 17 is positioned inside of the cup ot the dial 7 so that the cylindrical portion ot said dail overhangs the magnet as indicated in Figure 8. When the magnet 17 is driven in rotation by the movement ol' the car, its motion with respect to the metal dial 7 will generate in that Vdial eddy currents which reacting on the rotating magnet will tend to carry the dial along with the magnet. A torsional ertort is thereby applied to the dial tending to rotate the same on its spindle 8 against the resistance of the spring 9. Since the pull exerted by the magnet 17 on the dial is proportional to the speed of rota*- tion, the deflection of the dial 7 will also be proportional to that speed and its indicaE tions `will vary accordingly. The parts so tar described may be of any well known construction suitable for the purpose and are all 'well known in the art, so that description in further detail will be unnecessary.

In accordance with this invention the dial 7 may be equipped with one or more stops 1S and 19 adapted to be engaged by a catcn 29 mounted on the top plate 11. The stops 18 and 19 may be formed by bendingup punched ont portions of the dial cup. The catch 20 is shown as a spring` mounted `by meansfof a screw 21 on the plate 11. The stops 1S land 19 and the catch 2O are so positioned relatively to one another that when the dial moves to successive speed indicat` ing positions, the stop 18 will tlrst pass under the catch 2Oy which yields to allow such passage, and thereafter snaps behindthe stop 19 so as to prevent the return ot the dial to normal position. The stop 18 may be positioned 'lor instance to arrest the dial after passing` the indication corresponding; to say tifteenmiles per hour. The stop 19 may be positioned so as to arrest the dial at a higher indication as, for instance, twenty-tive miles per hour as shown in Figure 2. After the dial has moved beyond one of these speeds, one or the Vother or". the stops will be held by the catch and prevent tl e dial from returning' to normal, though still free to move beyond the stop, and this condition will be maintained until the dial is released by manually lifting the catch 29. Sincethe mechanism is entirely'enclosed by a suitablecasing as in the ordinary practice, the casing may be provided with the necessary seals to prevent unauthorized access to `the mechanism. The driver of the car is, tl'ieret'ore, unable to o-bliterate the indication which shows that an excessive speed has been reached by his carv some time duringthe days o aeration. llhen the caris brought in at night, an authorized person may open the casing andrelease the dial to normal position. In this way an indicatioir of the fact that the car hasbeen driven at an eX- cessive speed is'preserved until 1t can be examined by a properly authorized person'and the driver who habitually abuses his car can thus be detected.

lt is obvious that various changes may be made in details of construction without departing` from the spirit ol tiis invention; it is, therefore, to be understood that this invention is not to be limited to the specific details shown and described.

Having` thus described the invention, what is claimed is:

1. ln a speedometer, speed indicating mechanism including,` a dial which is freely movable to variant speed indicating positions and returns to normal, and means adapted to retain said dial, against return to normal, at a predetermined indicating position, in order to indicate that a certain speed has been exceeded.

2. In a speedometer, speed indicating` mechanism includingv a dial which is *freely movable to Variant speed indicating positions and returns to normal, a stop on said dial, and a catch cooperating; with said stop adapted' to retain said dial, against return to normal, at a predeternined indicating;l position, in order to indicate that a certain speed has been exceeded.

3. ln a speedometer, speed indicating` mechanism including a dial which is freely movable to 'variant speed indicating positions and returns to normal, and means adapted to retain said dial, against return to normal` at a'predetermined indicating positi on, while permitting movement of the dial beyond such position, in order to indicate that a certain speed has been exceeded.

in a speedometer, speed indicating mecha-mism incliiiding' a dial which is freely movable to variant speed indicating positions and returns to normal, a stop on said dial,and a yielding catch adapted to ireely ride over said stop when moving' in one direc-tion, in order to retain said dial, against return to normal, at a predetermined indicating position, in order to indicate that a certain speed has been exceeded.

lln testimony whereof l ailix vmjy'lsigirature this 10th day of July, 1923. A

DANEL F. HYLAND. 

